From: Thierry Reding <tred...@nvidia.com>
The fdt_for_each_subnode() iterator macro provided by this patch can be
used to iterate over a device tree node's subnodes. At each iteration a
loop variable will be set to the next subnode.
Signed-off-by: Thierry Reding <tred...@nvidia.com>
Signed-off-by: Maxime Ripard <maxime.rip...@free-electrons.com>
Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
---
cpukit/include/libfdt.h | 28 ++++++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/cpukit/include/libfdt.h b/cpukit/include/libfdt.h
index 36222fd4a6..911e548163 100644
--- a/cpukit/include/libfdt.h
+++ b/cpukit/include/libfdt.h
@@ -168,6 +168,34 @@ int fdt_first_subnode(const void *fdt, int offset);
*/
int fdt_next_subnode(const void *fdt, int offset);
+/**
+ * fdt_for_each_subnode - iterate over all subnodes of a parent
+ *
+ * @node: child node (int, lvalue)
+ * @fdt: FDT blob (const void *)
+ * @parent: parent node (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ * fdt_for_each_subnode(node, fdt, parent) {
+ * Use node
+ * ...
+ * }
+ *
+ * if ((node < 0) && (node != -FDT_ERR_NOT_FOUND)) {
+ * Error handling
+ * }
+ *
+ * Note that this is implemented as a macro and @node is used as
+ * iterator in the loop. The parent variable be constant or even a
+ * literal.
+ *
+ */
+#define fdt_for_each_subnode(node, fdt, parent) \
+ for (node = fdt_first_subnode(fdt, parent); \
+ node >= 0; \
+ node = fdt_next_subnode(fdt, node))
+
/**********************************************************************/
/* General functions */
/**********************************************************************/
--
2.13.7
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